Prospective study of breast tomosynthesis as a triage to assessment in screening

There is limited evidence on the role of 3D mammography with tomosynthesis in breast screening, although early studies suggest that it may improve specificity. We prospectively evaluated the effect of integrating 3D mammography as a triage to assessment in 158 consecutive recalls to assessment (recalled in standard 2D-mammographic screening) in asymptomatic subjects. Radiologists provided 3D mammography-based opinion as to whether recall/assessment was warranted or unnecessary, and all subjects proceeded to assessment. 3D triage was positive (confirmed the need for assessment) in all 21 subjects with breast cancer (there were no false negatives), and would have avoided recall in 102 of 137 (74.4%) subjects with a negative/benign final outcome in whom 3D triage did not recommend recall. Proportion of true negative 3D triage (as a proxy for potential reduction in recalls) was slightly higher in dense than non-dense breasts, did not differ across age-groups, but was significantly associated with the type of lesion seen on imaging (being highest for distortions, asymmetric densities, and lesions with ill-defined margins). While the simulation design may have over-estimated the potential for 3D mammography triage to reduce recalls, this study clearly demonstrates its capability to improve breast screening specificity and to reduce recall rates. Future studies of 3D mammography should further assess its role as a recall-reducing strategy in screening practice and should include formal cost-analysis.